Return a blank in date field

Collect doesn't actually return any null date type. There's a bug report

You can change the order of your questions, and only ask the date of birth
when relevant:
(select_one ask_dob) Reason for not answering [birth-date provided; -
refused to answer; - does not know; ]
(date dob) relevant=selected(${ask_dob}, 'birth-date provided')


··· On Sunday, May 26, 2013, TLG wrote:


I'm trying to create a question with date input, but where no date is
returned if the subject does no answer the question.

My ideal is to use field-list to ask on the same page:

(date) What is respondent's date of birth?
(select_one) Reason for not answering [- refused to answer; - does not
know] etc

And the ideal would be that if the surveyor clicks 'refused to answer', no
value would be returned for the date question, rather than the default.

I don't suppose anyone has any tips on achieving this?

Many thanks for thinking about it,



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Hi guys, I am just seeing this question and was asking if there is a way to check if a date field, if not set as required has no value entered so that I can use it in a skip pattern. I have tried using the ${date_field}='' but that doesnt seem to work. Is there an easy way way to achieve that?

I dunno what version of Collect you are using, but checking for blank should work. Can you attach a very simple two question form that shows what you are trying?

Looks like Checking if a non required date field is blank has the solution!